From EP 0 644 149 A1 a handrail drive for an escalator is known. The known handrail drive has a drive device and a pressure device. Between the drive device and the pressure device a handrail is guided and pressure rollers of the pressure unit face the upper side of the handrail. Defined as the upper side is that side of the handrail on which the user of the escalator places their hand in order to hold themselves by the handrail. The drive device further has rollers which are assigned to one part of the pressure rollers, wherein, between the rollers of the drive device and the handrail, a drive-belt passes. In order to taughten the drive-belt, the drive-belt is also passed around a drive-sheave and a taughtening sheave. In operation, the pressure rollers press the handrail against the driven drive-belt, whereby the drive-belt is supported by the rollers of the drive device. The press-on force with which the pressure rollers act on the handrail is generated by a spring of the pressure device.
The handrail drive which is known from EP 0 644 149 A1 has the disadvantage that a large constructive height results, since the pressure rollers are initially borne in an arrangement that is farther away from the upper side of the handrail. This arrangement experiences pressure from the spring of the pressure device, which is even farther away from the upper side of the handrail. Since such handrail drives are normally arranged in the balustrade skirt, on account of their constructive height they must be arranged at the side of the step-band. This inevitably results in a wider escalator construction. However, because of the building dimensions, and for a predefined constructive width, the operators of an escalator or moving walk wish for a step-band or pallet-band that is as wide as possible, in order to achieve a transportation performance of the transportation system that is as high as possible, and to increase the transportation comfort for the users. Further, the handrail drive that is arranged at the side of the step-band can also result in deeper pits in the building, in order that the handrail drive, in particular the spring of the handrail drive, has sufficient space.
The task of the invention is to propose a handrail drive for the purpose of driving a handrail of a transportation system which, for a predefined constructive width of the transportation system, enables the use of a step-band or of a pallet-band which is as wide as possible, and which is optimized in relation to its constructive height.